TJ 

WO 


-NRLF 


B   M   S3D   M5b 


GIFT   OF 
Arthur  E.   Mono  aster 


ircular  WM  No.  506 


Westinghouse  Turbo- 


EAST    PITTSBUR.G.F'A. 


E", 


Westinghouse  Turbo- 

cy 


DURING  the  17  years  that  have 
elapsed  since  the  American 
rights  for  the  manufacture  of 
the  Parsons  steam  turbine  were 
acquired  and  the  Westinghouse  Ma- 
chine Company  and  the  Westinghouse 
Electric  &  Manufacturing  Company 
jointly  commenced  the  building  of 
turbo-generators  there  has  been  a 
complete  revolution  in  the  design  of 
electric  power  plants.  The  superior 
economy  of  the  turbo-generator  unit, 
not  only  in  steam  consumption,  but  in 
first  cost,  attendance  and  in  mainten- 
ance as  well,  and  the  reduction  it  has 
effected  in  general  plant  investment,  in 

real  estate,  buildings,  and  foundations,  has  practically  eliminated  the  large 
slow-moving  reciprocating  engine-driven  sets  from  the  serious  consideration  of 
the  modern  power  plant  engineer  and  designer. 

A  10,000-kilowatt  turbo-generator  set  readily  fits  into  the  space  required 
by  a  reciprocating  engine-driven  set  of  one-third  the  capacity,  and  its  cost  does 
not  exceed  the  average  price  paid  for  such  a  reciprocating  engine-driven  set. 
To  provide  for  extensions  in  metropolitan  plants,  in  congested  districts,  where 


726303 


Westinghouse  Turbo- Alternators 

the  cost  of  real  estate  is  unusually  high,  it  is  now  considered  justifiable  to 
discard  reciprocating  engine  and  generator  equipment  of  the  most  efficient 
,and,  serviceable  character  and  to  replace  it  with  turbine-driven  apparatus. 


The  Steam  Turbine 


The'gefiefai  idea'  of  a  steam  turbine  engine  is  almost  as  old  as  history 
itself.  But  it  lay  dormant  for  many  centuries,  because  there  was  no  machinery 
of  sufficiently  high  speed  to  be  suitable  for  driving  with  this  type  of  motor. 
Inventive  genius  requires  a  definite  stimulus,  and  in  the  case  of  the  steam 
turbine  the  stimulus  was  undoubtedly  furnished  by  the  introduction  and 
rapid  development  of  alternating-current  electrical  machinery — another  of  the 
many  examples  of  Westinghouse  pioneering  that  has  so  completely  justified 
itself  that  the  bitterness  of  the  opposition  it  encountered  is  almost  forgotten. 
The  American  people  as  a  nation  are  much  more  conservative  than  is  generally 
believed;  they  are  inclined  to  regard  innovations  rather  skeptically  until 
their  worth  is  established.  However,  when  the  utility  of  any  device  of  a 
mechanical  nature  is  once  recognized,  it  is  adopted  in  no  half-hearted  war 
and  its  application  and  further  development  are  carried  out  on  a  scale  of 
unprecedented  magnitude. 

When,  in  1895,  the  Parsons  steam  turbine  was  first  introduced  into  this 
country,  it  was  not  received  with  much  enthusiasm.  It  was  practically  five 
years  before  it  was  accorded  any  general  public  approval,  and  it  would  doubt- 
less have  been  considerably  longer  in  obtaining  recognition,  had  it  not  been 
that  one  of  the  allied  Westinghouse  interests — The  Westinghouse  Air  Brake 
Company — had  the  courage  to  install  a  plant  of  four  400-kilowatt  units.  This 
plant,  which  is  still  in  operation,  was  watched  with  the  utmost  interest  by 
leading  engineers  and  soon  demonstrated  the  reliability,  economy,  and  general 
attractiveness  of  the  steam  turbine  as  a  prime  mover  for  direct  connection 
to  alternating-current  generators.  From  that  time  on  the  growth  in  public 
favor  of  the  Westinghouse  Parsons  turbo-generator  units  has  been  phenomen- 
ally rapid  and  extensive. 

While  the  Westinghouse  Machine  Company  commenced  its  turbine  work 
under  the  American  patents  of  the  Honorable  Charles  A.  Parsons,  which  it 
purchased  outright,  it  has  been  no  mere  copyist,  but  has  from  the  first  worked 
along  original  and  progressive  lines.  For  example,  it  first  demonstrated  the 
practicability  of  single-cylinder  units  of  large  powers.  In  1901,  it  built  and 
installed  for  the  Hartford  Electric  Light  &  Power  Company,  Hartford,  Conn., 
a  turbine  of  2000  kilowatts  capacity  in  one  cylinder.  Up  to  that  time  no  single- 
cylinder  turbine  of  larger  than  500  kilowatts  capacity  had  been  built,  and  even 
with  separate  high  and  low-pressure  cylinders,  1000  kilowatts  was  then  the 
record  size.  Notwithstanding  predictions  of  failure,  this  machine  broke  down 
the  barriers  of  ultra-conservatism,  and  established  the  confidence  that  has  made 
possible  the  mammoth  engines  that  are  in  common  use  today.  It  has  made 
the  Company  willing  to  assume  the  responsibility  for  the  still  larger  units  that 
are  in  contemplation. 

The  combination  impulse  and  reaction  turbine,  and  the  double-flow 
design,  which  makes  it  possible  to  build  turbines  of  larger  capacities  and 
higher  rotative  speeds  than  would  otherwise  be  possible,  are  both  instances 


Westinghonse  Turbo- A  Iternators 


Westinghouse  Turbo- Alternators 

of  Westinghouse  progress! veness  and  originality.  This  Company  also  intro- 
duced the  governor-controlled  by-pass  for  automatically  taking  care  of  over- 
loads. 

Reaction  vs.  Impulse  Turbines 

The  elementary  principles  of  the  steam  turbine  are  now  so  generally 
known,  and  there  is  so  much  literature  on  the  subject  available,  that  any 
extended  theoretical  discussion  would  be  superfluous.  Broadly  speaking,  steam 
turbines  are  of  two  general  classes;  those  employing  the  reaction  principle 
and  those  employing  the  impulse  principle. 

In  the  reaction  turbine,  approximately  one-half  of  the  expansion  in  any 
one  stage  takes  place  in  the  stationary  blades,  imparting  to  the  steam  a 
velocity  substantially  equal  to  that  of  the  moving  blades,  so  that  it  enters 
them  without  impact.  The  remainder  of  the  expansion  takes  place  in  the 
moving  blades,  the  spaces  between  which  gradually  grow  smaller  from  the 
inlet  to  the  exit  side  of  the  turbine  forming  a  ring  of  moving  nozzles.  The 
velocity  imparted  to  the  steam  by  reason  of  the  expansion  occurring  in  the 
moving  blades,  produces  a  reactive  effort  on  these  blades  which  turns  the 
rotor  of  the  turbine.  This  effect  is  very  similar  to  that  produced  by  water 
issuing  from  an  ordinary  hose  nozzle. 

In  turbines  of  the  impulse  type  the  complete  expansion  for  any  one  stage 
takes  place  in  the  stationary  blades  or  nozzles,  and  the  steam  is  delivered  to 
the  moving  blades  with  a  velocity  somewhat  more  than  double  that  of  the 
blades.  The  passages  between  the  moving  blades  are  of  uniform  or  even 
slightly  increasing  cross  section  from  inlet  to  outlet.  The  moving  blades 
check  and  reverse  the  velocity  of  the  steam  current  and  the  reluctance  of  the 
steam  current  to  having  its  direction  and  velocity  altered  gives  rise  to  a  force 
against  the  blades  which  sets  the  rotor  in  motion. 

Each  of  these  two  general  classes  of  turbines  has  its  partisans,  and  doubt- 
less always  will  have.  In  Westinghouse  later  practice  a  combination  of  the 
two  principles  is  utilized  in  such  a  way  that  all  the  advantages  of  both  are 
obtained  with  none  of  the  disadvantages  of  either. 

The  use  of  a  single-impulse  element  for  the  first  stage  of  the  expansion 
is  desirable,  inasmuch  as  it  replaces  without  any  appreciable  sacrifice  of  economy, 
a  considerable  number  of  rows  of  reaction  blading  in  the  least  efficient  part  of 
a  reaction  turbine,  and  makes  possible  a  shorter  and  consequently  stiff er  rotor. 
For  the  intermediate  and  low-pressure  sections,  in  which  the  volume  of  the 
steam  is  sufficient  to  require  reasonably  long  blades  moving  at  considerable 
velocities,  an  extended  experience  confirms  the  belief  that  reaction  blading 
has  a  decided  economic  advantage. 

The  all-impulse  type  necessitates  a  rotor  built  up  of  discs  mounted  on  a 
shaft  of  small  diameter,  in  order  that  the  circumferential  clearance  between 
the  shaft  and  the  diaphragms  separating  the  pressure  chambers  may  be  as 
small  as  possible,  so  that  the  considerable  pressure  drops  between  adjacent 
stages  will  not  cause  too  much  leakage. 

In  the  reaction  type  the  pressure  drops  between  adjacent  stages  are  very 
much  smaller,  and  the  body  of  the  rotor  may  be  built  up  in  the  form  of  a  hollow 
drum.  The  drum  construction  is  much  stiffer  than  the  shaft  and  disc  design, 
and,  it  is  believed  much  safer.  When  a  disc  is  heated  it  develops  internal 


Westinghouse  Turbo-Alternators 


Fig.  2— A  10,000-Kva.,  11,000-Volt,  Three-Phase,  60-Cycle,  1800  R.P.M.  Unit  at  the  Plant  of  the 
City  Electric  Company,  San  Francisco 


Fig.  3— Three  5500-Kva.  and  Two  8000-Kva.,  11,000-Volt,  Three-Phase,  25-Cycle,  750  R.P.M. 
Units  and  Two  3000-Kva.,  11,000-Volt,  Three-Phase,  60-Cycle,  1200  R.P.M.  Units. 
Generating  Station  of  the  Pennsylvania  Tunnel  &  Terminal  Railroad 
Company,  Long  Island  City,  New  York 


Westinghouse  Turbo-Alternators 

strains  that  are  impossible  of  calculation,  and  which  are  liable  to  start  cracks 
in  the  metal,  resulting  in  many  instances  in  complete  rupture.  On  the  other 
hand,  in  a  rotor  made  up  of  a  comparatively  thin  cylindrical  drum  of  con- 
siderable diameter,  and  rings  of  large  bore,  no  such  strains  are  encountered. 
Again,  the  drum  construction  of  rotor  makes  the  turbine  very  much  more 
accessible  for  examination  and  repairs.  In  most  of  the  later  designs  of  West- 
inghouse turbines,  the  upper  half  of  the  cylinder  can  be  lifted  without  inter- 
fering with  the  governor,  steam  chest,  or  pipe  connections.  With  the  special 
lifting  gear  furnished  with  each  turbine  as  a  part  of  the  tool  equipment,  the 
rotor  is  removed  in  a  very  short  time. 

A  comparison  of  the  actual  operations  of  dismantling  a  Westinghouse 
turbine  and  a  multi-stage  impulse  turbine  of  any  standard  design  whatsoever, 
will  demonstrate  the  superiority  of  the  former  as  regards  general  accessibility 
in  the  most  forcible  and  convincing  manner.  In  the  Westinghouse  combina- 
tion impulse  and  reaction  turbines,  only  one  impulse  element  is  used  so  that 
no  interstage  packing  is  required,  and  consequently  the  drum  and  ring  con- 
struction of  the  rotor  can  be  maintained. 

Variations  in  Design 

The  development  of  high-speed  alternating-current  generators  of  large 
capacities,  has  made  it  desirable  to  make  certain  radical  departures  from  the 


By-pass          Sfeam 
Inlet-  Inlet. 


-  Dummies 


Equilibrium  Pipe 


Fig.  4 — Section  of  a  Parsons  Type  Single-Flow  Turbine 

conventional  Parsons  design.  The  original  Parsons  design,  and  three  West- 
inghouse variations  thereof,  are  shown  diagrammatically  in  Figs.  4,  6,  9  and  11. 
The  Single-Flow  Type — Fig.  4  illustrates  the  original  single-flow  Parsons 
type.  Steam  is  admitted  at  A  to  an  annular  chamber  in  the  casing.  From 
this  point  the  steam  passes  alternately  through  rings  of  fixed  and  moving  blades, 
of  progressively  increasing  lengths,  on  the  small  diameter  of  the  drum  or  rotor, 
expanding  in  volume  as  it  passes  through  the  successive  rings  of  blades.  When 
the  volume  of  the  steam  has  increased  to  the  extent  that  the  blades  on  this 
small  diameter  of  drum  and  casing  would  have  to  be  inconveniently  long  to 
provide  passageway  for  it  at  a  sufficiently  moderate  velocity,  the  diameters 
of  the  drum  and  casing  are  increased  for  the  next  stage  of  the  expansion.  The 
available  area  of  the  steam  passage  through  the  blades  is  a  fairly  constant 


Westinghouse  Turbo-Alternators 


Fig.  5 — 100,000  Kw.  in  One  Room 
Kent  Avenue  Station  of  the  Brooklyn  Rapid  Transit  Company 


Westinghonse  Turbo-Alternators 

percentage  of  the  product  of  the  mean  circumference  of  the  blade  ring  multi- 
plied by  the  height  of  the  blades. 

If  the  mean  diameter  of  the  blades  in  the  second  stage  be  increased  to 
about  1.42  times  that  of  those  in  the  first  stage,  the  area  through  each  blade 
ring  per  inch  of  blade  height  will  be  1.42  times  that  through  the  first  stage 
rings.  On  account  of  the  larger  diameter,  the  mean  speed  of  the  blades  will 
also  be  1.42  times  that  of  the  blades  in  the  first  stage  and  consequently  the 
velocity  of  the  steam  through  the  blades  in  the  second  stage  may  be  1.42  times 
that  in  the  first  stage.  Now  if  the  area  through  the  second  stage  blades  per 
inch  of  height  and  the  velocity  of  the  steam  through  the  blades,  are  both  1.42 
times  as  great  as  in  the  first  stage,  then  to  pass  the  same  volume  of  steam  per 
second  the  blades  in  the  second  stage  need  be  only  one-half  as  high  as  those 
in  the  first  stage. 

As  the  steam  expands  in  the  second  stage,  its  volume  will  increase  until 
the  blade  heights  required  again  become  excessive.  The  drum  diameter  is 


Reaction    Element    — 


Exhaust 


-  No2Zle    Chamber 
--Impulse  Wheel 


-  -  Dum  my 


Fig.  6 — Section  of  a  Combination  Impulse  and  Reaction  Single-Flow  Turbine 


again  increased,  and  the  blade  heights  on  the  enlarged  diameter  are  reduced. 
Expansion  proceeds  along  this  third  or  low-pressure  stage  through  progres- 
sively increasing  blade  rings  until  the  pressure  of  the  steam  falls  to  that  of  the 
exhaust. 

Impulse  and  Reaction  Single-Flow  Type — Fig.  6  illustrates  a  modifica- 
tion of  the  single-flow  design  in  which  the  smallest  barrel  of  reaction  blading  is 
replaced  by  an  impulse  wheel.  Steam  is  admitted  to  the  nozzle  block  A,  is 
expanded  in  the  nozzles  and  discharged  against  a  portion  of  the  periphery  of 
the  impulse  wheel.  The  intermediate  and  low-pressure  stages  are  identical 
with  the  corresponding  stages  in  the  design  illustrated  in  Fig.  4.  The  sub- 
stitution of  the  impulse  element  for  the  high-pressure  section  of  reaction 
blading  has  no  influence  one  way  or  another  on  the  efficiency.  That  is  to  say 
the  efficiency  of  an  impulse  wheel  is  about  the  same  at  the  least  efficient  section 
of  reaction  blading.  This  design  is  attractive,  however,  in  that  it  shortens 
the  machine  materially,  and  gives  a  stiffer  design  of  rotor. 

The  entering  steam  is  confined  in  the  nozzle  chamber  until  its  pressure 
and  temperature  have  beet,  materially  reduced  by  expanding  through  the 
nozzles.  As  the  nozzle  chamber  is  cast  separately  from  the  main  cylinder, 
the  temperature  and  pressure  differences  to  which  the  cylinder  is  subjected 
are  correspondingly  lessened.  However,  probably  on  account  of  its  small 

10 


Westinghouse  Turbo-Alternators 


Fig.  7— Two  500-Kva.  and  One  625-Kva.,  600-Volt,  Three-Phase,  60-Cycle,  3600  R.P.M.  Units 
Pressed  Steel  Car  Company,  McKees  Rocks,  Pa. 


Fig.  8— An  H80-Kva.,  Two-Phase,  440-Volt,  40-Cycle,  Low-Pressure  Turbo-Generator  Unit, 
American  Iron  &  Steel  Company,  Lebanon,  Pa. 

11 


Westinghouse  Turbo-Alternators 

diameter  at  the  high-pressure  section,  the  straight  Parsons  type  has  always 
shown  itself  to  be  adequate  for  all  of  the  steam  pressures  and  temperatures 
encountered  in  ordinary  practice.  The  principle  advantage  of  the  high-pres- 
sure impulse  element,  is  that  without  any  sacrifice  of  economy,  it  shortens  the 
rotor  to  such  an  extent  as  to  make  a  double-flow  design  practicable. 

The  Double-Flow  Turbine — The  maximum  economical  capacity  of  a 
single-flow  turbine  is  limited  by  the  rotative  speed.  The  economical  velocity 
at  which  the  steam  may  pass  through  the  blades  of  the  turbine  depends  on  the 
velocity  of  the  moving  blades.  The  capacity  of  the  turbine  depends  on  the 
weight  of  the  steam  passed  per  unit  of  time,  which  in  turn  depends  on  the 
mean  velocity  and  the  height  of  the  blades.  For  a  given  rotative  speed,  the 
mean  diameter  of  blade  ring  practicable  is  limited  by  the  allowable  stresses 
due  to  centrifugal  force,  and  there  is  a  practical  limit  for  the  height  of  the 
blades. 

Now  if  we  make  the  rotative  speed  only  half  as  great,  the  maximum 
diameter  of  the  rotor  may  be  doubled  and,  without  increasing  the  height  of 


Reaction  Element 


Impulse.,  Wheel 


Reaction  Element 


Exhaust  -•  -I-*- 


--Exhaust 


Fig.  9 — Section  of  a  Double-Flow  Turbine 


the  blades,  the  capacity  of  the  turbine  will  be  doubled.  So  with  the  single- 
flow  steam  turbine  as  well  as  with  the  single-crank  reciprocating  engine,  there 
is  a  practical  limiting  economical  capacity  for  any  given  speed.  If  this  limit 
is  reached  with  a  single-crank  reciprocating  engine,  we  may  produce  a  .unit 
of  double  the  power  at  the  same  speed  by  coupling  two  single-crank  engines 
to  one  shaft.  We  accomplished  similar  results  by  making  a  double-flow  tur- 
bine which  is  in  effect,  as  will  be  seen  from  Fig.  9,  two  single-flow  turbines 
made  up  in  a  single  rotor  in  a  single  casing  with  a  common  inlet  and  two  exhausts. 
Steam  enters  the  nozzle  block  A,  acts  on  the  impulse  element,  and  then  the 
current  divides,  one-half  of  the  steam  going  through  the  reaction  blading  at 
the  left  of  the  impulse  wheel ;  the  remainder  passes  over  the  top  of  the  impulse 
wheel  and  through  the  impulse  blading  at  the  right. 

Semi-Double-Flow  Type — Fig.  11  is  a  modification  in  which  the  inter- 
mediate section  of  reaction  blading  is  single-flow,  and  the  low-pressure  section 
only  is  double-flow.  This  would  be  analogous  to  a  triple  compound  recipro- 
cating engine  with  one  high-pressure,  one  intermediate  pressure  and  two  low- 
pressure  cylinders — a  design  not  at  all  uncommon  in  very  large  engines  in  which 
the  required  dimensions  of  a  single  low-pressure  cylinder  would  be  prohibitive. 
Such  turbines  are  useful  for  capacities  greater  than  is  desirable  for  a  single-flow 
turbine,  and  which  are  still  below  the  maximum  possibilities  of  a  double-flow 
turbine  of  the  same  speed.  In  such  machines  the  best  efficiency  is  secured  by 

12 


Westinghouse  Turbo- Alternators 


tfS 


»i  I 

Kg 


a 

ll 
=  • 


a 


13 


Westinghouse  Turbo-Alternators 

making  the  intermediate  blading  in  a  single  section  large  enough  to  pass  the 
entire  quantity  of  steam. 

A  "dummy"  similar  to  those  used  on  the  single-flow  Parsons  type,  shown 
at  the  left  of  the  impulse  wheel,  compels  all  of  the  steam  to  pass  through  the 
single  intermediate  section  of  the  reaction  blading,  and  balances  the  end  thrust 
due  to  this  section.  When  the  steam  issues  from  the  intermediate  section, 
the  current  is  divided,  one-half  passing  directly  to  the  adjacent  low-pressure 
section,  while  the  other  half  passes  through  the  holes  shown  in  the  periphery 
of  the  hollow  rotor  and  through  the  rotor  itself,  beyond  the  dummy  ring,  into 
the  other  low-pressure  section  at  the  left-hand  end  of  the  turbine. 

There  are  sound  logical  engineering  reasons  for  the  existence  of  these 
several  types,  viz.,  single-flow,  double-flow,  and  semi-double-flow.  The  double- 
flow  turbine  is  not  offered  as  a  design  that  is  inherently  superior  to  the  single- 
flow  design,  but  it  is  offered  for  use  under  conditions  for  which  the  single-flow 


Single  Flow 
Reaction  Element 

Reaction  Element 


--  Impulse   Wheel 
~"  Dummy 
Reaction   Element 


Exhaust  - 


.--  Exhaust 


Nozzle   Chamber 
Fig.  11 — Section  of  a  Semi-Double-Flow  Turbine 

machine  is  unsuitable.  Similarly,  the  semi-double-flow  is  recommended  only 
for  conditions  which  it  can  meet  more  satisfactorily  than  either  of  the  other 
types. 

Special  Turbines 

While  this  publication  is  devoted  to  a  consideration  of  the  steam  turbine 
solely  as  a  prime  mover,  taking  steam  at  boiler  pressure,  and  using  all  of  its 
steam  for  producing  mechanical  energy,  the  turbine  principle  is  nevertheless  so 
flexible  as  to  be  capable  of  many  special  adaptations.  Two  of  these,  viz: 
low-pressure  or  exhaust  turbines,  and  "bleeder"  turbines  are  very  important 
and  interesting. 

Low-pressure  turbines  use  exhaust  steam  from  non-condensing  engines 
and  are  valuable  as  an  adjunct  to  existing  plants  for  the  purpose  of  increasing 
economy  and  capacity  with  a  minimum  outlay  for  new  equipment.  Examples 
of  low-pressure  turbine  installations  are  shown  in  the  illustrations  on  pages 
25  and  31. 

Bleeder  turbines  are  for  use  in  plants  which  are  required  to  furnish,  not 
only  power,  but  also  considerable  and  varying  quantities  of  low-pressure  steam 
for  heating  purposes.  In  these  turbines  a  part  of  the  steam  after  it  has  done 
work  in  the  high-pressure  stages  may  be  diverted  to  the  heating  system,  and 
the  remainder  expanded  through  the  low-pressure  blading  and  exhausted  into 


14 


Westinghouse  Turbo-Alternators 


15 


Westinghouse  Turbo-Alternators 

the  condenser.  In  this  way  none  of  the  energy  of  the  heating  steam,  due  to 
the  difference  of  pressure  between  the  boiler  and  the  heating  system,  is  wasted. 
On  the  other  hand  if  no  steam  is  required  for  heating  purposes,  the'  turbine 
operates  just  as  efficiently  as  though  the  bleeder  feature  were  absent.  A 
general  view  of  the  bleeder  turbine  is  shown  in  Fig.  30.  The  weighted  valve 
on  the  top  of  the  cylinder  regulates  the  pressure  and  quantity  of  steam  bled  to 
the  heating  system. 


^ 


-  ^^^ ^^^ji^j^rfta*"""*' 


Fig.  13— A  Single-Flow  Rotor 


Fig.  14 — A  Double-Flow  Rotor 


Some  Details  of  Construction 

Rotors — Figs.  13,  14  and  15  illustrate  respectively  single-flow,  double- 
flow,  and  semi-double-flow  rotors.  These  rotors  are  built  up  of  hollow 
steel  shafts  or  drums,  which  are  machined  on  the  inside  as  well  as  on  the  out- 
side. The  shaft  sections  are  enlarged  or  flanged  at  one  end  and  securely  fixed 
in  the  drums.  The  drum  diameter  corresponds  to  the  root  diameter  of  the 
smallest  rings  of  blading.  The  larger  diameters  of  blading  sections  are  mounted 
in  groups  on  separate  steel  drums  which  are  carefully  balanced  and  pressed 
on  the  central  drum.  The  "dummies"  on  the  single-flow  Parsons  type,  and 
on  the  Westinghouse  semi-double-flow  design  are  also  made  up-  of  separate 
steel  rings  pressed  on  the  central  drum  so  that  if  they  should  be  injured  by 
careless  adjustments,  they  can  be  easily  removed  and  replaced  by  new  ones. 


Westinghouse  Turbo- Alternators 

The  Westinghouse  impulse  blading  is  shown  in  detail  in  Fig.  16.  It 
is  made  of  extruded  metal  and  is  of  generous  section.  The  blades  are  sepa- 
rated by  steel  packing  pieces,  and  blades  and  packing  pieces  are  locked  together 


Fig.  15 — A  Semi-Double-Flow  Rotor 

by  steel  pins  so  arranged  as  to  present  the  strongest  possible  resistance  against 
shearing.  The  method  of  assembling  the  components  is  evident  from  the  illus- 
tration. The  grooves  in  the  impulse  wheel  are  somewhat  wider  than  the 
blades,  and  have  an  overhanging  shoulder  on  one  side. 

The  blades  and  packing  pieces  are  notched  oruone  side,  and  when  in  place 
the  notches  engage  with  the  overhanging  shoulder  on  the  one  side  of  the  ring 
groove.  The  other  side  of  the  ring  groove  is  slightly  undercut  in  dovetail 


Fig.  16 — Westinghouse  Impulse  Blading 

fashion.  When  the  blades  and  packing  pieces  are  set  in  their  grooves,  the 
space  between  the  blades  and  the  dovetail  side  of  the  groove  is  filled  in  with 
a  series  of  pairs  of  steel  wedges.  These  wedges  are  beveled  in  both  directions 
viz.,  lengthwise  and  crosswise,  so  that  when  set  up  in  pairs  they  fit  snugly 


17 


Westinghouse  Turbo-Alternators 

against  the  side  of  the  blades,  and  the  undercut  side  of  the  ring  groove,  so 
that  they  cannot  be  loosened  or  thrown  out  by  centrifugal  force. 

The  section  of  the  blade  at  its  root  is  cut  away  much  less  than  any  with  other 
form  of  fastening,  and  consequently,  it  has  greater  strength  to  resist  centrifugal 
strains.  The  wedges,  while  affording  the  utmost  security  as  a  means  of  locking 
the  blades  in  place,  can  nevertheless  be  easily  removed  without  special  appli- 
ances, in  case  it  should  be  necessary  to  replace  or  repair  the  blading.  The 
impulse  blades  are  shrouded  to  prevent  the  steam  from  spilling  over  the  ends, 
as  shown  in  Fig.  17,  which  is  a  view  of  a  portion  of  a  single-double  flow 


Fig.  17 — Portion  of  a  Combination  Impulse 
and  Reaction  Rotor 


Fig.  18— Guide  Blade  Section 


rotor  showing  a  section  of  the  finish  impulse  blading,  and  also  a  little  of  the 
reaction  blading  and  the  '  'dummy' '  ring. 

There  are  two  rows  of  blades  on  the  single-impulse  element,  and  the  steam 
issuing  from  the  first  row  is  redirected  onto  the  second  row  by  a  short  section 
of  stationary  guide  blades  shown  in  Fig.  18. 

The  reaction  blading  exhibits  a  marked  improvement  over  older  practice. 
It  is  made  of  phosphor-bronze,  drawn  to  the  proper  section,  heat  treated  and 
cut  to  length.  The  root  ends  are  slightly  "upset"  in  a  "bulldozer"  and  a 
small  hook  or  shoulder  formed  on  one  side  as  shown  in  Fig.  20.  The  grooves 
in  the  rotor  and  cylinder  are  of  dovetail  section,  and  have  a  small  auxiliary 
groove  of  rectangular  cross-section  in  the  bottom.  The  steel  packing  pieces 
are  beveled  on  the  sides  to  fit  snugly  in  the  dovetail  grooves  and  the  shoulders 
formed  on  the  lower  ends  of  the  blades  project  down  into  the  auxiliary  grooves, 
and  hook  under  the  packing  pieces  so  that  they  could  not  be  pulled  out  without 
actually  shearing  the  metal.  The  slight  thickening  at  the  roots,  caused  by 


18 


Westinghouse  Turbo- A  Uernators 


19 


Westinghouse  Turbo-Alternators 


TWO- 1250  KVA.,600  VOLT.  60  CYCLE,  TURBINE  GENERATOR  UNITS. 
DARTMOUTH  MFG.  CORPORATION,  NEW  BEDFORD,  MASS. 


THREE  2000  KVA., 6600  VOLT.  25  CYCLE,A.C. TURBINE  GENERATOR  UNITS. 
CON6PESSIONAL  POWER  PLANT,  WASHINGTON,  D.C. 


Westinghouse  Turbo-Alternators 


Z500  W*,t  WOO  KVA.,2  PHASE,440  VOLT,  60  CTOE,  TURBINE 
6CNERATOR  UNITS.  B.F.  GOODRICH  COMPANY,  AKRON,  OHIO. 


JBBINE  GENERATOR  WOT. 
.KANSAS  CITY.  MO. 


750  W.,240  VOLT,  60  CYCLE, A.C  JURBJNE  GENERATOR  UNIT. 
BROWN  &  SHARP  MF6.CO.  PROVIDENCE.  R.I . 


Westinghouse  Turbo-Alternators 


the   "upsetting"  in   forming  the  hook  or  shoulder,  adds  very  greatly  to  the 
strength  of  the  blades. 

With  the  largest  sizes  of  reaction  blading,  double  wedges  are  used- in  one 

side  of  the  blading  groove, 
which  are  similar  to  those 
used  for  securing  the  im- 
pulse blades.  The  outer 
ends  of  the  blades  are  tied 
together  with  the  now  well- 
known  '  'comma' '  lashing, 
The  blades  are  punched 
with  comma-shaped  holes 
as  shown  in  Fig.  23  and  a 
wire  of  the  same  section  is 
threaded  through  these 
holes.  After  the  blades  are 
straightened  and  gauged, 
the  part  of  the  lashing  wire 
that  in  section  corresponds 
to  the  tail  of  the  comma,  is  curled  over,  forming  a  rigid  separator,  or  distance 
piece  between  the  blades.  For  the  longest  reaction  blades,  two  lashings  are 
used,  one  at  the  middle  of  the  blade  and  one  near  the  outer  end. 

Cylinder — In  the  cylinder  design,  care  has  been  taken  to  eliminate  inso- 


Packing  Pieces 


Assembly 


Fig.  20— Reaction  Blading 


Figs.  21  and  22 — Two  Views  of  Nozzle  Chamber  with  Stationary  Guide  Blade  Section  Attached 

far  as  possible,  all  ribs,  equalizing  ports,  and  other  features,  which  would  result 
in  an  unnecessarily  complicated  and  irregular  casting  that  would  be  likely  to 
be  affected  by  strains  resulting  from  temperature  changes.  Whenever  dummy 
packings  are  used,  as  in  the  semi -flow  Parsons  type  and  in  the  semi-double- 


22 


Westinghouse  Turbo-Alternators 

flow  combination  type,  they  are  made  up  in  removable  rings  as  illustrated  in 
Fig.   24.     In  the  combination  impulse  and  reaction  turbines,  the  nozzle  cham- 


Original 


Calked 


Blade  Punched 


Blade  Lashed 


Fig.  23— Westinghouse  Comma  Lashing 

bers  are  also  independent  castings.     The  nozzle  chamber  is  illustrated  in  Figs. 
21    and  22.     The  root  section  of  stationary  guide  blades  between  the  first 
and  second  rows  of  impulse  blades,  is  attached  to  the  nozzle  chamber.     Figs. 
21    and    22  show    respectively  the 
front  and  rear  views  of  the  nozzle 
chamber  with  the  guide  blade  sec- 
tion attached.     There  are  two  noz- 
zle chambers  in  each  turbine,  the 
primary  and  the  secondary.     The 
secondary  comes  into   action  only 
when  the  turbine  is  loaded  above 
its  normal  or  rated  capacity. 

Spindle  Gland  Packing — The 
various  metallic  and  fibrous  pack- 
ings which  give  excellent  results 
both  as  to  wear  and  tightness  in  a 
stuffing  box  for  a  reciprocating  pis- 
ton rod,  are  not  at  all  satisfactory 
when  applied  to  a  stuffing  box  on 
a  shaft  rotating  several  thousand 
times  a  minute.  In  general,  the 
packing  in  a  steam  turbine  is  sub- 
jected to  only  a  moderate  pressure 
difference,  i.e.,  the  difference  be- 
tween the  pressure  of  the  atmo- 
sphere, and  the  vacuum  at  the 
exhaust  end  of  the  turbine.  Instead 
of  preventing  the  escape  of  steam 
from  the  turbine,  the  office  of  the 

packing  is  to  prevent  air  leaking  into  it;  and  as  a  properly  designed  turbine 
makes  profitable  use  of  the  last  fraction  of  an  inch  of  vacuum  attainable,  it 
is  particularly  desirable  that  this  packing  should  be  tight. 

In  the  Westinghouse  turbines,  the  spindle  gland  is  packed  by  an  annular 
ring  of  water,  which  is  absolutely  tight,  and  which  does  not  cause  any  wearing 


Fig.  24 — Dummy  Packing 


23 


Westingkouse  Turbo-Alternators 


of  the  shaft.  A  bronze  casting  like  the  runner  of  a  small  centrifugal  pump 
(see  Fig.  13)  is  pressed  on  the  shaft,  and  rotates  in  an  annular  chamber 
surrounding  the  opening  in  the  end  of  the  turbine  cylinder  through  which  the 
shaft  projects.  Water  is  fed  to  this  annular  chamber,  and  under  the  action 
of  centrifugal  force,  it  builds  up  a  fluid  ring  or  wall  between  the  bronze  runner 
and  the  turbine  casing,  which  effectually  seals  the  opening,  and  which  is  strong 
enough  to  resist  a  pressure  of  more  than  30  pounds  per  square  inch.  The 
grooved  hubs  on  the  bronze  runner  constitute  an  ordinary  labyrinth  packing 

that  may  be  temporarily  sealed  with 
water  or  low-pressure  steam  while  the 
turbine  is  being  started,  and  before  it 
has  attained  the  speed  required  to 
make  the  centrifugal  water  packing 
effective. 

Governing — Fig.  25  is  a  view  of 
the  governor,  with  the  casing  removed. 
It  is  driven  from  the  main  shaft 
through  a  worm  gear,  and  is  unusually 
powerful.  The  ball  levers  and  the 
links  connecting  these  levers  to  the 
governor  sleeve,  are  all  pivoted  on  hard 
chrome  steel  knife  edges,  which  elim- 
inate frictional  disturbances.  The 
main  spring  surrounds  the  spindle 
and  bears  directly  on  the  governor 
sleeve.  A  small  auxiliary  spring,  with 
a  manually  or  electrically-operated 
tension  gear  for  making  small  speed 
adjustments  while  running,  is  con- 
nected to  the  governor  linkage.  It  is 
used  in  synchronizing  the  alternators 
or  in  distributing  the  electrical  load 
among  them. 

In  the  smaller  turbines,  the  gover- 
nor acts  directly  on  the  steam  admis- 
sion valves,  opening  first  the  primary  valve,  and  then,  if  necessary,  the  secondary 
valve,  after  the  primary  is  fully  open.  In  turbines  of  the  single-flow  Parsons 
type,  the  governor  actuates  two  small  valves  controlling  ports  leading  to  steam 
relay  cylinders  which  operate  the  admission  valves.  The  little  valve  controlling 
the  relay  cylinder  for  the  secondary  valve  has  more  lap  than  the  other  and 
consequently  does  not  come  into  action  until  the  primary  valve  has  attained 
its  maximum  effective  opening.  Fig.  28  shows  the  general  design  of  this 
type  of  valve  gear. 

Governors  for  the  larger  turbines,  particularly  those  of  the  combination 
impulse  and  reaction  double,  or  single  double-flow  type,  employ  an  oil-relay 
mechanism,  illustrated  in  Fig.  29  for  operating  the  steam  valves.  In  these 
turbines  the  lubricating  oil  circulating  pump,  maintains  a  higher  pressure  than 
is  required  for  the  lubricating  system.  The  governor  controls  a  small  relay 


Fig.  25 — Turbine  Governor 


24 


Westinghouse  Turbo- A Iternators 


Fig.  26— A  937-Kva.,  Three-Phase,  600-VoIt,  60-Cycle  Turbo-Generator  Unit,  Lorain 
Manufacturing  Company,  Pawtucket,  R.  I. 


Fig.  27 — An  8000-Kva.,  Two-Phase,  60-Cycle  Turbo- Genera  tor  Unit,  Peoples  Power 
Company,  Moline,  111. 


25 


Westinghouse  Turbo- Alternators 


valve  A ,  which  admits  pressure  oil  to,  or  exhausts  it  from  the  operating  cylinder. 
When  oil  is  admitted  to  the  operating  cylinder  raising   the    piston,    the 

lever  C  lifts  the  primary 
valve  E.  The  lever  D 
moves  simultaneously  with 
C,  but  on  account  of  the 
slotted  connection  with  the 
stem  of  the  secondary  valve 
F,  the  latter  does  not  begin 
to  lift  until  the  primary 
valve  is  raised  to  the  point 
at  which  its  effective  open- 
ing ceases  to  be  increased 
by  further  upward  travel. 
A  common  fault  of  most 
oil-relay  governing  systems 
is  that  they  are  sluggish  in 

Fig.  28— ValvelGear  With  Steam  Relay  their  action.       In  the  West- 

inghouse  designs,  the  oper- 
ating valve  A  is  connected  not  only  to  the  governor,  but  also  to  a  vibrator, 
which  gives  it  a  slight  but  continuous  reciprocating  motion,  while  the  gov- 
ernor controls  its  mean  position.  The  effect  of  this  is  manifested  in  a  slight 
pulsating  throughout  the  entire  relay  system,  which,  so  to  speak,  keeps  it 
'  'alive' '  and  ready  to  respond  instantly  to  the  smallest  change  in  the  position 
of  the  governor.  The  oil  relay  can  be  made  sufficiently  powerful  to  operate 
valves  of  any  size,  and  it  is  also  in  effect  a  safety  device  in  that  any  failure 
of  the  lubricating  oil  supply  will  automatically  and  immediately  shut  off  the 
steam  and  stop  the  turbine. 

Safety  Stop  Governor — Every  Westinghouse  turbine  is  fitted  with  a  simple, 
reliable  speed- 
limit  governor, 
which  is  wholly 
independent  of 
the  main  regu- 
lating governor 
and  its  driving 
gear.  Whenever 
the  turbine  at 
tains  the  over- 
speed  limit  to 
which  this  safety- 
stop  governor  is 
adjusted,  an  au- 
tomatic stop 
valve  is  tripped,  Fig  ^^  Gear  With  ou  Relay 

and    the    steam 

supply  is  shut  off.  When  it  is  desired  to  shut  the  turbine  down,  the  oper- 
ator, instead  of  closing  the  throttle  by  hand,  can,  by  exerting  a  pull  on  the 
governor  linkage,  make  the  turbine  speed  up  until  the  limit  governor  trips 


26 


Westinghouse  Turbo-Alternators 


Fig.  30— A  625-Kva.,  600-Volt,  60-Cycle,  Three-Phase  Automatic  Bleeder  Turbo-Generator 
Unit,  Lowell  Bleacheries,  Lowell,  Mass. 


Fig.  31 — A  300-Kva.,  440-Volt,  60-Cycle,  Three-Phase,  Turbo -Genera  tor  Unit  Installed  In  the 
Bernon  Mills  Plant,  Georgiaville,  R.  I. 

27 


Westinghouse  Turbo- A  Iternators 

the  automatic  stop  valve  and  in  this  way  assure  himself  that  the  safety-stop 
mechanism  is  in  condition  to  act  with  promptness  and  certainty  in  case  its 
protection  should  be  needed. 

Bearings — In  turbines  running  at  speeds  of  more  than  3000  revolutions 
per  minute  the  spindle  tends  to  rotate  on  its  gravity  axis  instead  of  on  its 
geometric  or  mechanical  axis;  of  course,  these  two  axes  are  made  to  coincide 
as  exactiy  as  possible,  but  a  difference  so  small  as  to  be  within  the  limit  of  error 
of  the  most  refined  methods  of  balancing,  might  set  up  disagreeable  vibrations 
when  the  turbine  is  running  at  full  speed. 

To  compensate  for  this  possible  condition,  the  bearings  on  high-speed 

turbines  are  made  up  of  several  concentric  tubes  with  slight  clearance  between 

them.     The  lubricating  oil  fills  these  clearances  with  a  viscous  film  which  forms 

an  elastic  cushion,  and  allows  the  spindle  to  find  its  true  center  of  rotation. 

This  nest  of  tubes  is  carried  in  a  cast-iron  sleeve  which  rests  in  a  pedestal. 

In  Fig.  32  the  nest  of  tubes  is  shown 
at  the  left,  and  the  supporting  sleeve  at 
the  right.  On  the  outside  of  the  sup- 
porting sleeve  are  four  steel  blocks  fitting 
in  slots  spaced  90  degrees  apart  and 
secured  with  screws.  These  blocks  ex- 
tend above  the  outer  circumference  of 
the  casting  and  are  machined  to  form 
a  section  of  the  surface  of  a  sphere. 
The  pedestal  has  a  corresponding  spher- 
ical bore,  so  that  the  combination  forms 

Fig.  32— Turbine  Bearing  a  self-aligning  ball  and  socket  bearing. 

The  steel  blocks  referred  to  above, 

are  backed  up  with  a  few  rolled-steel  shims,  the  thickness  of  which  are  multi- 
ples of  five  one-thousandths  of  an  inch.  By  transferring  these  shims  from  one 
side  of  the  bearing  to  the  other,  the  final  adjustments  for  centering  the  spindle 
in  its  casing  can  be  affected  with  the  utmost  nicety. 

In  the  larger  and  slower-running  turbines,  the  so-called  critical  speed  is 
never  reached  and  consequently  the  concentric  oil-cushioned  tubes  are  not 
required.  The  bearings  for  these  turbines  are  very  like  the  supporting  sleeve 
for  the  high-speed  turbine  bearings,  except  that  they  are  babbitt-lined  and 
made  in  halves. 

Lubrication — A  closed  oiling  system  through  which  a  continuous  circulation 
is  maintained  by  means  of  a  pump  geared  to  the  main  shaft  of  the  turbine, 
keeps  the  turbine  and  generator  bearings  flooded  with  oil  at  a  very  moderate 
pressure.  From  the  bearings,  the  oil  drains  through  a  strainer  into  a  col- 
lecting reservoir,  whence  it  is  pumped  through  a  cooler,  and  back  to  the  bear- 
ings. No  water-cooled  bearings  are  used  on  Westinghouse  turbo-generators. 
It  is  believed  to  be  safer,  more  convenient,  and  more  efficient  to  water-cool  the 
oil  in  the  course  of  its  travel  through  the  system. 

In  the  turbines  in  which  the  oil-relay  governing  system  is  employed,  and 
a  higher  pressure  is  maintained  by  the  pumps,  the  comparatively  small  quantity 
of  oil  required  for  operating  the  valve  mechanism  passes  to  the  relay  cylinder, 
whence  it  exhausts  into  the  cooler.  The  remainder  of  the  circulating  oil  dis- 

28 


Westinghouse  Turbo-Alternators 


Fig.  33 — A  937-Kva.,  Three-Phase,  600-Volt,  60-Cycle  Turbo-Generator  Unit,  Corr  Manufacturing 

Company,  East  Taunton,  Mass. 


Fig.  34— A  4000-Kva.,  Three-Phase,  2300-Volt,  60-Cycle  Unit  and- a  3500-Kva.  Unit  of  the  Same 
Characteristics,  Narragansett  Electric  Lighting  Company,  Providence,  R.  I. 


29 


Westinghouse  Turbo-Alternators 


5:?? 


Water  Rates- Lbs/KWHR. 
5500K.W  WP  Turbine 
74  th  St.  Station,  N.Y 
Tested  by  H.  G.  Staff 
\-l907-ISOLbs,  SB'Vacumn 
3-  19/0- 176  £&s.  ?S"?a'B  Vtoc. 
2-  B   Corrected  to  HSLbs  £8"Vac 
D-B"  Corrected  to  ISOLbs.  ?S"  Vfcc 


charges  directly  into  the  cooler  through  a  spring-loaded  pressure-reducing  valve, 
so  that  pressure  in  the  main  circulation  is  therefore  the  same,  whether  the  oil- 
relay  governing  system  is  employed  or  not. 

Economy — This  is  a  matter  that  depends  more  on  scientific  proportions 
than  on  the  general  type  of  turbine.  Published  reports  of  tests,  are  apt  to  be 
misleading,  unless  one  is  especially  skilled  in  interpreting  the  data  obtained. 
Until  the  principles  of  turbine  design  become  more  extensively,  and  more 
exactly  a  matter  of  public  information,  the  purchaser  will  have  to  rely  more 
on  the  knowledge,  experience,  and  integrity  of  the  builder,  than  on  any  theo- 
retical discussion  of  the  subject.  The  Westinghouse  Machine  Company  has 
the  most  extensive  steam-turbine  testing  plant  in  the  world.  It  has  conducted 
more  actual  tests  of  steam  turbines  than  any  other  manufacturer,  and  its  files 
of  test  records,  constitute  the  most  comprehensive  collection  of  dependable 
information  on  turbine  efficiencies  in  existence. 

Efficiency  guarantees  as  to  the  performance  of  Westinghouse  turbines 
are  made  with  the  expectation  that  they  may  have  to  be  demonstrated,  and 
not  with  the  hope  that  they  may  never  be  questioned.  Better  guarantees 

may  be  offered,  but  in  point  of 
actual  performance — the  only  thing 
that  really  counts — Westinghouse 
turbines  are  still  distinctly  in  the 
lead.  Those  who  are  interested  in 
examining  in  detail,  arid  analyzing 
efficiency  tests,  are  referred  to  a 
series  of  trials  on  the  10,000-kilo- 
watt  unit  installed  for  the  City 
Electric  Company,  San  Francisco, 
Cal.,  shown  in  the  illustration  on 
page  5.  These  tests  were  con- 
ducted by  the  J.  G.  White  Com- 
pany, and  were  reported  in  a  paper  presented  by  Mr.  S.  L.  Napthaly,  at  the 
annual  meeting  of  the  American  Society  of  Mechanical  Engineers,  at  New  York, 
in  December,  1910.  A  reprint  of  this  paper  will  be  sent  on  request. 

Permanency  of  Efficiency — Most  important  of  all,  however,  is  the  question 
of  the  permanency  of  the  efficiency.  In  this  connection  the  diagram,  Fig.  35, 
above  is  particularly  interesting,  in  that  it  shows  graphically  the  results  of  a 
test  of  a  5,500-kilowatt  Westinghouse  turbine  at  the  74th  Street  station  of  the 
Interboro  Rapid  Transit  Company,  New  York  City,  in  comparison  with  the 
results  of  a  test  of  the  same  machine  made  three  years  earlier.  These  tests 
were  made  under  the  direction  of  Mr.  H.  G.  Stott,  Superintendent  of  Motive 
Power,  and  at  the  date  of  the  last  test  the  unit  had  been  in  service  five  years 
and  two  months,  and  its  total  output  had  been  168,614,075  kilowatt-hours,  or 
70  per  cent  of  the  total  number  of  hours  multiplied  by  the  rated  capacity  of 
the  unit.  The  last  test,  far  from  indicating  any  deterioration  in  efficiency, 
shows  even  better  results  than  the  one  made  three  years  earlier. 

Naturally,  this  record  reflects  the  highest  type  of  good  management  and 
intelligent  supervision,  but  at  the  same  time  it  is  evidence  that  the  Westing- 
house  turbines  possess  the  inherent  qualities  that  make  this  sort  of  manage- 
ment and  supervision  worth  while. 

30 


4000  5000          6000 

Load  KW 


Fig.  35 — Curves  of  Turbine  Performance 


Westinghouse  Turbo- Alternators 

The  Generator 

Although  the  principle  of  operation  of  the  steam  turbine  and  that  of  the 
reciprocating  engine  are  decidedly  unlike,  the  principle  of  operation  of  the 
high-speed  turbine-driven  generator  does  not  differ  from  that  of  generators 
designed  for  being  driven  by  other  types  of  engines  or  by  water-wheels.  There 
are,  therefore,  with  the  turbine-driven  generator,  no  new  ideas  for  the  operator, 
who  is  familiar  with  the  older  forms  to  acquire.  That  the  proportions  of  such 
high-speed  machines  must  be  very  different  from  those  permissible  in  generators 
of  much  slower  speeds  is  obvious.  In  the  high-speed  machines '  the  rotor 


Fig.  36 — Westinghouse  Generator  for  Turbine  Drive 

diameter  is  small  and  is  of  relatively  greater  length  than  in  low-speed  generators. 
Special  ventilation  is  necessary.  The  high  peripheral  rotor  speeds  involve  new 
ideas  and  ideals  in  material,  design,  and  workmanship. 

Westinghouse  turbo-generators  have,  from  the  time  they  were  the  pioneers 
in  the  field,  formed  a  part  of  the  most  efficient  turbine  units  operating  in 
America.  Their  present  development  is  the  result  of  unremitting  investiga- 
tions, exhaustive  tests,  the  advantages  of  a  splendid  shop  equipment  and  the 
efforts  of  superior  engineering  talent. 

Type — From  the  first,  Westinghouse  turbo-units  have  been  of  the  hori- 
zontal type.  They  are  the  result  of  a  long  and  consistent  development  of 
this  one  type.  That  sound  judgment  was  used  in  selecting  this  construction 
is  evidenced  by  rapidly  decreasing  use  of  the  vertical  units. 

Armature  Construction 

Frame  and  Core — A  pleasing  appearance  results  from  the  use  of  a  cast- 
iron  frame  having  cast-iron  end-bells  bolted  to  each  of  its  ends.  The  frame  is 
of  the  box  girder  construction  which  provides  the  rigidity  required  to  firmly 

31 


Westinghouse  Turbo-Alternators 

hold  the  laminated  core.     It  also  provides  passages  through  which  the  warm 
air  is  conducted  away  from  the  generator. 

Ventilation — The  turbo-generator  gives  a  very  large  output  from  relatively 
little  material  in  a  small  space.  Therefore  the  losses  in  these  generators  that 
must  be  disposed  of  as  heat  are  very  large  per  unit  area.  This  necessitates 
plenty  of  cooling  air.  Well  designed,  well  located  devices  for  effectively  guiding 
its  flow  must  be  provided.  No  one  design  of  air-circulating  device  will  effi- 
ciently serve  for  turbo-generators  of  all  sizes  and  speeds.  The  Westinghouse 
method  is  to  affix  a  special  blower  (See  Fig.  44)  to  the  rotor.  It  creates  a 
flow  of  air  which  is  guided  by  enclosing  end-bells  (Fig.  37)  through  the  fan- 


D 


Fig.  37 — Generator  with  Half  of  End-Bell  Removed 

shaped  end  turns  of  the  armature  coils  (Fig.  40),  thence  into  the  interior  of 
the  machine.  Most  of  it  flows  through  the  air-gap  between  the  stator  and  the 
rotor.  Because  the  laminations  are  very  deep  and  the  volume  of  air  forced 
through  is  large,  the  ducts  (Fig.  42)  must  be  of  just  the  right  proportions 
and  must  be  accurately  located  to  insure,  with  economy  of  air  and  power, 
uniform  temperatures.  The  warm  air  collects  in  the  large  annular  spaces 
(Fig.  41)  within  the  frame  casting  and  is  ejected  downwardly.  Very  large 
generators  are  sometimes  ventilated  by  a  motor-driven  fan.  In  very  large 
stations  the  installation  of  such  an  auxiliary  is  justified  because  its  blower  is 
more  efficient  than  that  on  a  generator  shaft. 

Winding — Because  of  the  small  number  of  coils  in  a  turbo  machine  as 
compared  with  that  in  a  slow-speed  generator  of  the  same  kilovoltampere 
rating,  each  turbo-generator  armature  coil  carries  an  enormous  amount  of 
power  on  large  loads,  particularly  at  times  of  short-circuits  of  grounds  on  the 
external  circuit.  The  "throw"  of  the  coils  is  large,  leaving  a  considerable 
part  of  the  winding  in  the  end  turns  unsupported  by  the  armature  core.  For 
these  reasons  great  stresses,  which  are  dangerous  if,  effective  means  are  not 

32 


Westinghouse  Turbo-Alternators 


Fig.  38— Two  625-Kva.,  Two-Phase,  450-Volt,  60-Cycle,  Turbo-Generator  Units,  Sherwin 
Williams  Company,  Kensington,  111. 


Fig.  39— A  750-Kva..  Three-Phase,  2400-Volt,  60-Cycle,  Low-Pressure  Turbo-Generator  JJnlt, 
Penn  Mary  Coal  Company,  Possum  Glory,  Pa. 


33 


Westinghouse  Turbo-Alternators 

adopted  to  withstand  them,  may  exist  between  the  coils.  An  absolutely 
unique  and  perfectly  secure  form  of  armature  winding  has  been  invented  for 
use  in  Westinghouse  turbo-generators. 


Fig.  40— Armature  with  End-Bells  Removed  Showing  Method  of  Bracing 


Fig." 41— Dovetail  Grooves  in  Stator  Casting         Fig.  42— Laminations  in  Position  in  Stator  Casting 

The  copper  conductors  in  the  coils  are  of  such  cross-section  that  they  can 
be  made  rigid  and  insulated  satisfactorily.     The  manufacturer  is  more  inter- 


34 


Westinghouse  Turbo- Alternators 


ested  than  any  one  else  in  seeing  that  none  but  the  best  insulation  is  used.     It 
is  his  insurance.     Then  the  end  turns  are  given  the  fan-like  (Fig.  43)  form 
peculiar    to    Westinghouse    turbo- 
generator armature  coils.     This  con- 
struction affords  thorough  ventila- 
tion and  with  it  the  disposition  of 
the  coils  is  the  very  best  for  effective 
bracing  (Fig.  40). 

Cord  lashings  are,  except  in  the 
smallest  frames,  used  only  for  hold- 
ing in  the  small  spacing  blocks  be- 
tween the  coils.  They  are  not 
depended  on  to  support  the  coils. 
Malleable  iron  braces,  hard  maple 
blocks,  and  brass  or  steel  bolts  with 
brass  washers  are  used  to  withstand 
the  mechanical  stresses  imposed  on 
the  armature  coils  by  external  short 
circuits. 

Field  Construction 

Precedent  has  not  influenced 
the  Westinghouse  Company  to  try 
to  adapt  one  form  of  field  structure 
construction  for  all  capacities  and 
speeds.  The  radial  or  parallel  slot, 
the  integral  or  separate  shaft;  and 

the  semi-laminated  or  solid  disc  body  form  of  construction  is  each  used  for 
rotors  of  the  capacities  and  speeds  for  which  it  is  best  fitted.  A  record  of 
entire  freedom  from  any  operating  difficulty  has  been  maintained  for  several 
years  for  fields  built  within  that  period. 

Insulation — Every  field  is  insulated  solely  with  fire-proof  materials — mica 
and  asbestos — although  guaranteed  for  the  usual  low-temperature  rise. 


Fig.  43— Armature  Partially  Wound 


Fig.  44— A  Two-Pole,  Parallel  Slot  Field 

Radial  Slot  Construction — Very  small  generators,  have  fields  of  the  radial 
slot  construction  shown  in  Fig.  45.  The  rotor  diameters  are  so  small  that 
the  end  turns  of  the  winding  can  be  effectively  bound  into  place,  such  binding 
being  necessary  with  a  radial  slot  machine.  The  shaft  and  disc  are  a  one- 
piece  forging  of  steel. 


35 


Westinghouse  Turbo-Alternators 

The  parallel  slot  design  of   field    construction,    developed   only   by    the 
Westinghouse   Company,   is   best   utilized  in  two-pole  field  generators  up'to 


Fig.  45— A  Two-Pole,  Radial  Slot  Field 


Fig.  46— A  Four-Pole,  Parallel  Slot  Field 


Fig.  47— A  Four-Pole,  Radial  Slot  Field 

10,000-kilovoltampere  capacity  or  thereabout.  Fig.  49  shows  parallel  slot 
cylinders,  wound  and  ready  for  assembly.  The  large  holes  near  the  circumfer- 
ence of  the  cylinder  are  for  the  accommodation  of  the  bolts  that  hold  the  bronze 
end  disks  and  stub  shafts.  In  winding,  the  cylinders  are  mounted  on  a 
horizontal  turn-table  that  rotates  in  a  horizontal  plane.  The  copper  strap  field 
coil  winding  is  wound  turn  by  turn  under  pressure  and  strip  insulation  is  wound 
in  between.  When  completed  the  turns  are  held  rigidly  in  position  with  heavy 

36 


Westinghouse  Turbo- Alternators 

brass  wedges.  In  Fig.  44  the  rotor  has  been  completed.  A  perfectly  compact 
unit,  almost  indestructible  and  one  in  which  the  end  turns  are  securely  sup- 
ported, results. 

An  end  disc,  made  of  bronze  to  prevent  magnetic  leakage,  holds  the  stub 
shaft  and  is  bolted  to  each  end  of  the  steel  center.  When  the  leads  are  attached 
to  the  collector  rings  the  field  is  complete.  No  instance  of  operating  trouble 


Fig.  48— A  Two-Pole,  Parallel  Slot  Field 


(either  mechanical   or  electrical)    with  rotors  of  this  type  of  construction  has 

ever  been  reported  to  the  Westinghouse  Company.     Hundreds  are  in  service. 

Multipolar  fields  are  illustrated  in  Figs.  46    and  47.     Construction  such 

as  shown  in  Fig.  46  is  entirely  satisfactory  except  for  the  large  sizes  for  which 


Fig.  49— Parallel  Slot  Field  Cores 


Fig.  50 — Armatures  Under  Construction 

it  is  difficult  for  the  manufacturer  to  obtain  castings  promptly.  It  is  unneces- 
sary to  make  special  provision  for  end  turns.  The  shaft  is  integral  with  the 
field  center. 

For  very  large  fields  the  radial  slot  construction  is  used.  Through  the 
use  of  this  construction  the  use  of  large  steel  castings  is  avoided.  Fig.  47  illus- 
trates a  field  of  this  type. 

37 


Westinghouse  Turbo- Alternators 


£  S 

a  a 

f    u 

o  2 


«  a 
• 

II 


38 


Westinghouse  Turbo- A  Iternators 


39 


The  Westinghouse  Machine  Co, 


New  York 
Atlanta 
Boston 
Chicago 
Cincinnati 
Cleveland    - 
San  Francisco 
Denver 
Pittsburgh  - 
Philadelphia 
St.  Louis 
City  of  Mexico 


General  Offices  and  Works 

East  Pittsburgh,  Pa. 


SALES  OFFICES 


Ijp  Broadway 

ff 
^       -  Candler  Building 

201  Devonshire  Street 
39  South  La  Salle  Street 
1102  Traction  Building 
1117  Swetland  Building 
Hunt,  Mirk  &  Co.,  141  Second  Street 
Gas  and  Electric  Building 
-    Westinghouse  Building 
£03  North  American  Building 
-  Chemical  Building 
era,  Importadora  y  Contratista,  S.  A. 


Circular  W.  M.  507 


November,  1912 


TheWestinghouse 


SMALL  TURBINE-DRIVEN  OUTFITS 


Pumps  For  All  Purposes 


Generating  Units 


fr^X  I 


Centrifugal  Blo\vers 


EAST    PITTSBUR.G.RA. 


A  Non-Condensing  Turbine  Driving  the  Air  and  Circulating 
Pumps  of  a  Westinghouse  Leblanc  Condenser 


Westinghouse  Small  Turbine  Outfits 

THAT  turbines  are  by  all  means  the  most  satisfactory 
form  of  drive  for  auxiliaries  and  small  generating  units, 
is  generally  conceded  by  all  who  have  used  them  or 
have  had  opportunity  to  observe  their  performance.     By  every 
measure  which  the  station  owner  or  operator  applies  to  his 
apparatus,  they  surpass  reciprocating  machinery,  and  just  as 
the  large  turbine  effected   a  complete  change  in   main   unit 
practice,  so  now  this  type  of  prime  mover  is  becoming  the 
standard  for  exciter,  blower,  or  pump  drive. 

Without  enumerating  the  self-evident  advantages  of  tur- 
bines for  such  service,  this  pamphlet  deals  in  a  general  way 
with  the  product  of  The  Westinghouse  Machine  Company  in 
this  field,  including  not  alone  the  driving,  but  also  the  driven 
part  of  the  unit. 


Westinghouse  Small  Turbine  Outfits 

Centrifugal  Pumps 

For  fire  or  water  service,  irrigation,  condensing,  or  general  purposes, 
the  centrifugal  pump  has  almost  unlimited  application,  and  in  a  great 
majority  of  cases  the  turbine  furnishes  the  desirable  form  of  drive.  This 
is  particularly  true  of  such  pumps  when  used  in  and  about  power  houses. 


The  Westinghouse  Machine  Company  is  accordingly  prepared  to  furnish 
centrifugal  pumps  in  any  capacity  for  power  house  work,  including  boiler- 
feed,  hot-well,  circulating  and  general  service  pumps.  A  brief  descrip- 
tion of  the  types  built,  with  general  information  as  to  capacity  and 
size,  follows. 

Boiler  Feed  Pumps 

As  indicated  by  the  sectional  view  opposite,  the  centrifugal  boiler-feed 
pumps  built  by  this  Company  are  of  the  multi-stage,  double-suction  type. 
This  construction  has  several  decided  advantages  over  the  single-suction 
pumps,  largely  employed  in  the  past.  End  thrust,  a  constant  source  of 
trouble,  is  practically  eliminated,  no  balancing  pistons  being  necessary. 
The  double-suction  pump  may  also  be  operated  at  higher  speeds  for  equal 
capacity  and  efficiency,  thus  improving  the  economy  of  the  driving 
turbine  appreciably.  Floor  space  requirements  also  favor  this  construc- 
tion. 

A  particular  feature  of  the  design  is  the  ease  with  which  the  machine 
may  be  inspected  in  all  its  parts.  The  casing  and  its  heads  are  horizon- 
tally split,  and  the  upper  half  can  be  lifted  and  the  whirl  chambers  and 
runner  shaft  removed  without  disturbing  any  pipe  connections. 

The  use  of  large  shaft  diameters  is  made  possible  by  the  ample 
suction  passages,  insuring  a  rigid,  smoothly  operating  unit.  The  bearings 
are  ring-oiled,  large  reservoirs  being  provided  to  carry  the  oil.  The 
glands  are  soft  packed,  the  problem  of  evenly  packing  a  revolving  shaft 
being  overcome  by  a  simple  but  effective  system  which  involves  a  mini- 
mum of  wear  on  the  shaft  and  very  infrequent  necessity  of  re-packing. 


Westinghouse  Small  Turbine  Outfits 


It  is  accurate  to  state  that  the  pump  here  described  represents  the 
latest  development  in   the   building  of  centrifugal   boiler-feed   appara- 


tus, and  that  the  features  of  its  construction  embody  most  fully  the 
advantages  of  rotating  over  reciprocating  pumps  for  this  service. 

A  list  of  standard  sizes  with  closely  approximate  dimensions  follows: 


Westinghouse  Small  Turbine  Outfits 


Boiler  Feed  Pumps 


INLET 


a 

1 

Head 
in  Feet 

Pressure 
in  Lbs. 
Per  Sq.  In. 

Stages 

Length 

(A) 
With  Turbine 
Drive 

Width 
(B) 

Height 

(C) 

PIPE  SIZES 

Inlet 
(1) 

Discharge 
(2) 

150 
to 
230 

192-460 

287-690  I 
384-920 

83-200 
125-300 
166-400 

2 
3 
4 

7'  11" 
8'    6" 
9'  *0" 

2'  10" 

3'    4" 

5" 

4" 

225 
to 
350 

192-460 
287-690 
384-920 

83-200 
125-300 
166-400 

2 
3 

4 

7'  11" 
8'    6" 
9'    0" 

2'  10" 

3'    4"             5" 

4" 

295 

to 
458 

192-460 
287-690 
384-920 

83-200 
125-300 

](i(i    100 

o 

3 
4 

8'    8" 
9'    5" 
10'    1" 

3'    5" 

4'    7"             6" 

5" 

371 
to 
570 

192-460 
287-690 
384-920 

83-200 
125-300 
166-400 

2 
3 

4 

9'    0" 
9'    9" 
10'    3" 

3'    5" 

4'    7"             6" 

5"  . 

450 
to 
700 

192-460 
287-690 
384-920 

83-200 
125-300 
166-400 

2 
3 
4 

9'    6" 
10'    4" 
11'    1" 

3'  10" 

4'  11" 

8" 

6" 

590 

to 
920 

192-460 
287-690 
384-920 

83-200 
125-300 
166-400 

2 

3 
4 

10'    3" 
11'    1" 
11'  10" 

3'  10" 

4'  11" 

8" 

6" 

750 
to 
1160 

192-460 

287-690 
384-920 

83-200 
125-300 
166-400 

2 
3 
4 

11'    2" 
12'    2" 
13'    3" 

4'  10"         6'    4"           10" 

8" 

840      192-460 
to       287-690 
1190    384-920 

S3   200 
125-300 
166-400 

2 
3 
4 

12'    2" 
13'    5" 
14'    8" 

6'    6" 

7'  10" 

12" 

10" 

1480     192-460 
to       287-690 
2300    384-920 

83-200        2 
125-300        3 
166-400        4 

12'    2" 

13'    5" 
14'    8" 

6'    6" 

7'  10" 

12" 

10" 

Westinghouse  Small  Turbine  Outfits 


Circulating  and  General  Service  Pumps 

In  connection  with  jet  and  surface  condenser  work,  this  Company 
has  built  a  large  number  of  centrifugal  pumps  which  are  particularly 
adapted  to  low-head  service.  The  runners  are  of  the  double-suction  type, 
giving  large  ca- 
pacity for  small 
diameter,  which 
results  in  good 
efficiency  at 
economical 
speeds.  These 
pumps,  one  of 
which  is  shown 
by  the  photo- 
graph, may  be 
driven  by  tur- 
bines, motors,  or 
by  belt.  While 
primarily  de- 
signed to  handle 
water  for  con- 
densers, they 
are  available  for 
any  moderate 

head  service,  and  their  high  efficiency,  the  ease  with  which  they  may 
be  inspected,  and  their  rugged  construction,  make  them  generally  desir- 
able. These  pumps  are  built  in  a  complete  list  of  sizes  given  by  the 
following  table: 


DISCHARGE  (1) 


Gals. 
Per  Min. 

Head 
in  Feet 

Length 
A 

Width 
B 

Height 
C 

Discharge 
Piping 

750-  1000 

20  to  30 

4'  5" 

3'  2" 

2'  10" 

6" 

1500-  2000 

20  to  30 

5'  6" 

3'  2" 

2'  10" 

10" 

2500-  3000 

6'  7" 

3'  2" 

2'  10" 

12" 

4000-  5000 

20  to  30 

4'  9" 

3'  5" 

3'    0" 

14" 

6000-  7500 

20  to  30 

6'0" 

3'  5" 

3'    0" 

16" 

8000-12000 

20  to  30 

7'  3" 

3'  5" 

3'    0" 

18" 

15000-20000 

20  to  30 

5'  9" 

4'0" 

3'    6" 

24" 

23000-28000    . 

20  to  30 

7'  2" 

4'0" 

3'    8" 

32" 

30000-37500 

20  to  30 

8'  7" 

4'0" 

3'    6" 

36" 

Westinghouse  Small  Turbine  Outfits 


High  Efficiency  Low-Head  Pumps 
For  Large  Capacities 


One  reason  for  the  popularity  of  steam  turbines  for  auxiliary  drive 
is  that  the  exhaust  is  uncontaminated  by  oil,  and  is  therefore  pure  water 
for  boiler  feed.  As,  however,  relatively  high  speeds  should  be  used  for 
good  efficiency,  they  are  sometimes  unfitted  for  direct  connection  to 
pumps,  particularly  where  the  working  head  is  small.  An  example 
of  this  condition  is  the  centrifugal  circulating  pump  for  surface  con- 
densers, where  large  volumes  of  water  are  to  be  handled  against  total 
heads  seldom  exceeding  30  feet.  To  overcome  this  inconsistency  in 
speeds  and  at  the  same  time  retain  high  efficiency  in  both  pump  and 
turbine,  this  Company  makes  use  of  the  Flexible  Reduction  Gear  first 
employed  in  connecting  turbines  and  direct-current  generators.  A 
circulating  unit  built  on  this  plan,  is  shown  above. 

The  efficiency  of  the  gear  is  approximately  97  per  cent,  and  of  the 
pump  70  to  75  per 
cent,  with  heads  as 
low  as  15  feet.  Of 
course,  the  use  of 
the  gear  permits 
of  any  turbine 
speed  required  for 
high  efficiency. 
These  outfits  are 
built  with  one,  two 
or  three  double- 
suction  runners  on 
a  common  shaft, 
depending  upon  the 
desired  capacity. 
A  sectional  view  of 
a  two-runner  pump 
is  shown  herewith. 


Westinghouse  Small  Turbine  Outfits 


If  it  is  desired,  motor  drive  may  of  course  be  employed  instead  of 
the  turbine  and  gear.  The  following  table  gives  closely  approximate 
data  on  these  pumps. 


I 


o 


Capacity 
Gal.  Per  Min. 

Head 

Speed 

Number             LENGTH 

Width 
B 

Height 
C 

Discharge 
Piping 

ners             A         |        P 

8000-13000 

10.0-25.0 

200-325 

1         16'  3" 

6'  3" 

7'0" 

6'    1" 

] 

8000-13000 

11.5-28.5 

200-325 

1      j  16'  5" 

6'    5" 

7'  2" 

6'    6" 

i   30" 

8000-13000 

12.8-32.0 

200-325 

1      i  16'  7" 

6'    7" 

7'  4" 

6'  11" 

] 

16000-26000 

10.0-25.0 

200-325 

2        19'  1" 

8'    7" 

7'0" 

6'    1" 

] 

16000-26000     11.5-28.5 

200-325 

2        19'  5" 

8'  11" 

7'  2" 

6'    6" 

i   36" 

16000-26000 

12  .  8-32  .  0 

200-325 

2        19'  9" 

9'    3" 

7'  4" 

6'  11" 

i 

24000-39000 

10.0-25.0 

200-325 

3        22'  0" 

10'  11" 

7'0" 

6'    1" 

1 

24000-39000 

11.5-28.5 

200-325 

3        22'  6" 

11'    5" 

7'  2" 

6'    6" 

42" 

24000-39000 

12.  8-32.  O1  200-325 

3        23'  0" 

11'  11" 

7'  4" 

6'  11" 

J 

Westinghouse  Small  Turbine  Outfits 


Condensate  and  General  Service  Pumps 

In  applying  Westinghouse  Leblanc  Air  Pumps  to  surface  condensers 
it  is  often  convenient  to  handle  the  condensate  by  a  centrifugal  pump 
mounted  on  the  same  shaft. 


These  small  centrifugal  pumps  are  also  arranged  for  separate  motor 
or  turbine  drive.  They  are  built  with  single-stage,  double-suction  run- 
ners, and  the  design  is  such  that  direct  or  alternating-current  motor 
speeds  are  suitable. 

The  total  head  in  handling  condensate  averages  about  60  feet. 
With  slight  modification,  these  pumps  are  therefore  available  for  small  and 
medium  capacity  general  purposes  against  heads  not  exceeding  125  feet. 

A  list  of  sizes  with  approximate  dimensions,  is  given  below. 


CAPACITY 

Speed              Head 

Length 
A 

Width 
B 

Height 
C 

Discharge 
Piping 

Lbs. 
Per  Hour 

Gals. 
Per  Min. 

20000 

401 

!  1400-2000 

50-125 

36" 

34" 

24" 

3" 

30000 

601 

1400-2000    50-125 

36" 

34" 

24" 

3" 

50000 

lOOi 

1400-2000    50-125 

38" 

31" 

25" 

4" 

75000 

l.W 

1400-2000    50-125 

38" 

31" 

25" 

4" 

I  00000 

200 

1400-2000 
1400-2000 

50-125 

40" 

34" 

2(5" 

5" 

150000 

300 

50-125 

40" 

34" 

26" 

5" 

200000 

400 

1400-2000 

50-125 

40" 

35" 

2S" 

6" 

300000 

600 

1400-2000 

50-125 

42" 

35" 

28" 

6" 

400000 

800 

\        1400-2000    50-125 

42"             35" 

28" 

8" 

Westinghouse  Small  Turbine  Outfits 


Small  Capacity  Centrifugal  Blowers 

For  Low  and  Intermediate  Pressures 

The  turbine  or  motor-driven  blowers  built  by  The  Westinghouse 
Machine  Company,  are  of  the  shallow  vane  centrifugal  type. 

The  machines  are  particularly  suited  to  forced  draft  work,  gas- 
blowing,  or  furnishing  blast  for  cupolas.  The  distinctive  characteristic 
of  the  blowers  is  their  efficiency,  which  averages  60  per  cent  at  rating. 


^ 

*^>s 

65 

*-•  — 

£F/ 

6 

/ 

X 

^. 

\ 

60 

5 

/ 

^L, 

—     —  . 

_ 

-^ 

*£ 

5A 

VOL. 

\ 

55 

Q: 

UJ 

4 

/ 

/ 

JJ^ 

& 

•  —  ^. 

•^ 

^^ 

50 

\0 

fe 

3 

/ 

£ 

< 

^ 

45 

6X 

•v. 

£ 

2 

tt 

40 

O 

<d 

; 

UJ 

1 

O 

fT" 

CO 
CO 

EN* 

:RG 

Y  a 

~DK 

JCH/ 

<\/?G 

£  M 

:LOC 

j/rv 

A/01 

r  IN 

CLt 

DEt 

i 

u» 
k 

LU 
£ 

N  C 

OMf 

>UT 

A/G  £:F/= 

7C/£ 

NCY 

kl 

Q. 

c 

> 

c 

> 

> 

1 

c 
c_ 

> 

c 

> 
) 

o 
cf 

o 

c> 

M 

•<r 
<\j 

o 

i 

o 
cf 
^t 

VOLUM 

E-CU.  FT. 

PER  MINUT 

E 

It  will  further  be  noted  on  the  accompanying  curve,  that  the  range  of 
this  efficiency  is  very  great,  extending  from  60  to  150  per  cent  of  the 
rated  capacity  of  the  blower.  A  third  advantage,  is  the  large  allowable 
variation  in  capacity  for  a  small  change  in  discharge  pressure,  a  desirable 

feature  in  nearly  all  installa- 
tions of  blowing  apparatus. 
A  fourth  desirable  feature  is 
the  fact  that  for  a  given  pres- 
sure there  is  only  one  value  of 
the  volume  discharged.  This 
is  of  great  advantage  when 
the  blower  is  to  be  operated 
in  conjunction  with  other 
blowing  machinery,  since 
there  will  be  a  stable  division 
of  load  between  the  two  or 
more  machines  operating,  if 
they  have  this  characteristic. 
An  accompanying  photo- 
graph shows  a  blower  and 
driving  turbine  of  our  make. 
This  apparatus  is  also  avail- 
able for  motor  drive  when 


Westinghouse  Small  Turbine  Outfits 


desired.     The  following  table  gives  closely  approximate  data  on  the 
capacity  and  dimensions  of  these  outfits. 


Double-Flow  Two- Bearing  Type 


Class 

Runner 
Diam. 

Speed 

Press. 

Capacity 

A 

B 

C 

DISCHARGE 
OPENING 

I 

II 

2A 

22^" 

2500 
4000 

2.4 
6.2 

11,000 
17,800 

3'  4" 

4'  8" 

4'  3" 

30" 

30" 

2A 

39" 

800 
1900 

2.2 
12.6 

22,100 
53,000 

3'  4" 

8'  2" 

8'0" 

36" 

36" 

3A 

39" 

800 
1600 

2.2 
8.9 

27,650 
55,200 

3'  9" 

8'  2" 

S'O" 

40" 

40" 

4A 

39" 

800 
1600 

2.2 
8.9 

33,200       ,,  9/, 
66,000 

8'  2"       8'  0" 

50" 

50" 

2B 

22^" 

2f>00 
4000 

5.8 
15.0 

14,000 
22,400 

3'  4" 

4'  8"       4'  3" 

30" 

30" 

2B 

39" 

800 
1900 

5.3 
30.0 

28,400       ,,  .„ 
68,000 

81  nil 
/ 

8'  0" 

36" 

36" 

3B 

39" 

800 
1600 

5.3 
21.3 

35,500       ,,  q// 
70,800 

81  nil 
A 

S'O" 

40" 

40" 
50" 

4B 

39" 

800 
1600 

5.3 
21.3 

42,600 
85,000 

4'  2" 

8'  2" 

S'O" 

50" 

2C 

22^" 

2f)0() 
4000 

12.5 
32.0 

16,600 
36,800 

3'  4" 

4'  8" 

4'  3" 

30" 

30" 

2C 
3C 
4C 

39" 

800 

1000 

11.4 
65.0 

32,000 
76,000 

3'  4" 

81  nn 
£ 

S'O" 

36" 

36" 

39" 

800 

1(H)() 

11.4 
46.0 

40,000 
80,000 

3'  9" 

81  nil 
£1 

S'O" 

40" 

40" 

39" 

800 
1600 

11.4 
46.0 

48,000 
96,000 

4'  2" 

S'  2" 

S'O" 

50" 

50" 

2D 

22^2" 

2500 
4000 

17.3 

(4.  r, 

22,000 
35,600 

3'  4" 

4'  8" 

4'  3" 

30" 

30" 

2D 

39" 

800 
1900 

16.0 
90.0 

40,000 
94,600 

3'  4" 

8'  2" 

S'O" 

36" 

36" 

3D 

39" 

800 
1600 

16.0 
64.0 

50,000 
100,000 

3'  9" 

8'  2" 

S'O" 

40" 

40" 

4D 

39" 

800 
1600 

16.0 
64.0 

60,000 
120,000 

4'  2" 

8'  2" 

S'O" 

50" 

50" 

10 


Westinghouse  Small  Turbine  Outfits 


Single-Flow  Overhung  Type 


Class 

Runner 
Diam. 

Speed 

Press. 
In.  of 
Water 

Capacity 

Length 
A 

Width 
B 

Height 
C 

Discharge 
Opening 

I 

II 

1A 

22^" 

2500 
4000 

2.4 

6.2 

5,500 
8,900 

10" 

4'  8" 

4'  3" 

20" 

20" 

1A 

39" 

800 
1900 

2.2 
12.6 
~2.2 
8.9 

11,050 
26,500 

10" 

8'  2" 

8'0" 

26" 

26" 

2A 

39" 

800 
1600 

16,600 
33,000 

1'    8" 

8'  2" 

8'0" 

30" 

30" 

IB 

22K" 

2500 
4000 

5.8 
15.0 

7,000 
11,200 
14,200 
34,000 

10" 

4'  8" 

4'  3" 

20" 

20" 

IB 
2B 

39" 

800 
1900 

5.3 

30.0 

10" 

8'  2" 

8'  0" 

26" 

26" 

39" 

800 
1600 

5.3 
21.3 

21,300 
42,500 

1'    8" 

8'  2" 
4'  8" 

8'0" 

30"          30" 

1C 

22)4" 

2500 
4000 

12.5 
32.0 

8,300 
13,400 

10" 

4'  3" 

20" 

20" 

1C 

39" 

800 
1900 

11.4 
65.0 

16,000 
38,000 

10" 

O/     f)lt 

o    A 

8'0" 

26" 

26" 

2C 

39" 

800 
1600 

11.4 
46.0 

24,000 
48,000 

1'    8" 

8'  2" 

8'0" 

30" 

30" 

ID 

22^" 

2500 
4000 

17.3 

44.5 

11,000 
17,800 

10" 

4'  8" 

4'  3" 

20" 

20" 

ID 

39" 

800 
1900 

16.0 
90.0 

20,000 
47,300 

10" 

8'  2" 

8'0" 

26" 

26" 

2D 

39" 

800 
1600 

16.0 
64.0 

30,000 
60,000 

1'    8" 

8'  2" 

8'  0" 

30" 

30" 

11 


Westinghouse  Small  Turbine  Outfits 


Generating  Units 

As  an  auxiliary  in  large  stations,  where  it  is  important  to  reduce 
attendance  to  a  minimum,  or  as  a  main  unit  in  smaller  plants  where 
reliability  is  highly  essential,  the  small  turbine  generating  unit  is  now 
generally  accepted  as  the  standard.  The  Westinghouse  Machine  Com- 
pany builds  a  very  complete  line  of  these  units  which  are  described  below. 
The  particular  characteristic  of  the  apparatus  is  its  co-ordination  of 
turbine  and  generator  design.  This  most  important  factor  in  the  success 
of  such  units  is  well  exemplified  in  those  built  by  this  Company. 


Direct-Current  Sets 

These  units  are  built  in  sizes  from  1  to  150  kilowatts  for  non-condens- 
ing service. 


The  100  and  150-kilowatt  machines  are  also  built  in  the 


12 


Westinghouse  Small  Turbine  Outfits 


condensing  type.  The  standard  voltage  is  125,  although  from  75-kilo- 
watts  up,  250-volt  generators,  either  two  or  three-wire,  are  furnished 
if  desired. 

A  25-kilowatt,  125-volt  set  and  a  100-kilowatt,  250-volt  set  are 
shown  by  the  cuts.  Although  somewhat  different  in  detail,  these 
machines  are  all  of  the  same  type.  The  turbine  wheel  is  mounted  on  the 
generator  shaft  and  overhangs  one  of  the  two  self-aligning  bearings. 
These  are  ring-oiled  in  the  smallest  machines,  and  in  the  larger,  are 
flooded  by  a  pump  driven  from  the  shaft.  The  operation  of  the  units  is, 
therefore,  entirely  automatic,  a  safety  stop  being  provided  which  would 
shut  the  machine  down  if  the  governor  became  disabled. 

The  following  table  gives  closely  approximate  data  on  these  units. 


Non-Condensing 


PIPE  SIZES 

Capacity 

Speed 

Voltage 

Length 

(1) 

(2) 

1-kw. 

4000              125 

3'     1"               14" 

19" 

W 

1" 

10-kw. 

6000 

125 

5'    0" 

2'    0" 

2'    5" 

IK" 

3" 

25-kw. 

3500 

125 

5'  9" 

2'  8" 

3'  3" 

2K" 

4" 

50-kw. 

3000 

125 

7'  10" 

4'  6" 

4'  7" 

2^" 

6" 

75-kw. 

2750 

125 

8'  4" 

4'  6" 

4'  9" 

4" 

9" 

75-kw. 

2750 

250 

8'  4" 

4'  6" 

4'  9" 

4" 

9" 

100-kw. 

2400 

125 

9'  6" 

5'  1" 

5'  1" 

4" 

9" 

100-kw. 

2400 

250 

9'  6" 

5'  1" 

5'  1" 

4" 

9" 

150-kw. 

2200 

125 

11'  3" 

5'  1" 

5'  6" 

4" 

12" 

150-kw. 

2200 

250 

9'  7"  :  5'  1" 

5'  6" 

4" 

12" 

Condensing 


100-kw. 
100-kw. 
150-kw. 
150-kw. 


2400     125 

11'  3" 

4'  11"  !  5'  7" 

3" 

14" 

2400 

250 

11'  3" 

4'  11"    5'  7" 

3" 

14" 

2200 

125 

14'  2" 

5'  1"    5'  9" 

3" 

14" 

2200 

250 

11'  6" 

5'  1"    5'  9" 

3" 

14" 

13 


Westinghouse  Small  Turbine  Outfits 

Alternating  Current 

The  cut  below  shows  a  100-kilowatt,  60-cycle,  alternating-current 
turbo-generator  set  with  a  direct-connected  exciter.  The  machine  shown 
is  designed  for  condensing  service.  A  non-condensing  unit  is  shown 
opposite.  There  is  a  small  constructional  difference  between  the  two 


units.  For  non-condensing  service,  the  turbine  wheel  is  of  the  overhung 
type,  as  is  the  case  in  the  direct-current  units.  The  condensing  units 
have  three  bearings,  two  outboard  and  one  between  the  turbine  and 
generator.  The  rotor  of  such  a  unit  is  shown  below.  As  the  steam 
volumes  at  vacuum  pressures  are  considerably  greater,  it  is  also  necessary 
to  use  larger  casings  and  nozzles.  In  operating  principle,  the  machines 
are  the  same,  consisting  of  a  single  impulse  wheel  upon  which  the  steam 
is  directed  several  times  in  order  to  entirely  absorb  its  velocity  energy. 


Sixty  cycles  being  practically  invariably  employed  in  America  as 
the  standard  frequency  for  small  units,  these  machines  all  operate  at 
3600  r.p.m.  They  can  be  equipped  with  direct-connected  exciters  or  not, 
as  is  desired. 


14 


Westinghouse  Small  Turbine  Outfits 


Capacity 

LENGTH 

Width 
(B) 

Height 
(C) 

PIPE  SIZES 

Unit 
(A) 

Exciter 
(D) 

Steam 
(1) 

Exhaust 
(2) 

100-kw. 
150-kw. 
200-kw. 
300-kw. 


14'  1" 
14'  5" 
16'  8" 
17'  6" 


3'0" 
3'0" 
3' 2" 
3'  6" 


Non-Condensing 

4' 9" 
4'  9" 
5' 6" 
5'  6" 


4'  4" 
4'  4" 
5'  5" 
5' 5" 


4" 
4" 
5" 
5" 


10' 
10' 

18' 
18' 


Condensing 


100-kw. 

14'  8" 

3'0" 

4'  5" 

4'  6" 

3" 

14" 

150-kw. 

15'  0" 

3'0" 

4'  5" 

4'  6" 

3" 

14" 

200-kw. 

16'  8" 

3'  2" 

4'  6" 

4'  6" 

4" 

18" 

300-kw. 

17'  6" 

3'  6" 

4'  6" 

4'  8" 

4" 

18" 

15 


Westinghouse  Small  Turbine  Outfits 

Small  Turbine  Construction 

The  apparatus  described  on  the  various  pages  of  this  catalogue, 
although  now  available  for  motor  drive,  was  originally  to  be  driven  by 
Westinghouse  small  turbines.  In  order  to  completely  cover  the  power 
turbine  field,  this  Company  builds  small  turbines  of  the  impulse  type 

ranging  in  normal  capacities 
from  10  to  500  horsepower, 
for  any  condition  of  speed, 
steam  pressure,  and  vacuum 
or  back  pressure. 

The  first  consideration  in 
the  design  of  these  machines 
has  always  been  simplicity. 
The  cut  shows  the  active 
principle  of  the  machines. 
In  each  case  they  consist  of  a 
single  disc  of  boiler-plate  steel, 
carrying  on  the  periphery 
nickel-iron  blades.  Steam, 
after  expansion  in  a  suitable 
nozzle,  passes  through  these 
blades,  delivering  to  them 
part  of  its  velocity  energy. 
On  leaving  the  blades  it 
enters  a  reversing  chamber 
which  again  redirects  it  onto 
the  blades.  This  process  is 
repeated  as  many  times  as 
necessary  to  make  efficient 
use  of  the  energy  in  the  steam. 
This  is  diagrammatically 

shown  by  the  figure  below.     Where  it  is  necessary  to  handle  large  volumes 
of  steam,  as  in  the  case  of  condensing  operation,  it  is  convenient  to  use 


STEAM    INLET 


a  wheel  such  as  is  shown  opposite,  which  wheel  is  of  the  condensing 
type.  In  any  event,  however,  the  power  of  the  turbine  is  developed1 
on  a  single  wheel,  and  all  the  complication  of  several  wheels  with 


16 


Westinghouse  Small  Turbine  Outfits 


diaphragms  and  trouble- 
some packing  between 
them  is  eliminated. 

This  simplicity  of 
connstruction  involves 
practically  no  sacrifice  in 
efficiency  of  the  machine, 
and  is  undoubtedly  the 
prime  factor  in  the  suc- 
cess of  turbine  drive  for 
auxiliary  apparatus,  since, 
as  a  rule,  this  is  installed 
in  more  or  less  inaccessible 
places.  The  most  satis- 
factory unit,  assuming 
reasonable  efficiency,  will 
therefore  be  the  one  re- 
quiring the  least  atten- 
tion, which  in  turn  is,  of 
course,  the  one  operating  upon  the  simplest  principle. 

The  blades,  which  as  noted  before,  are  made  of  nickel  iron,  have 
roots  which  set  in  a  groove  turned  in  the  edge  of  the  disc,  and  steel  pins 
are  driven  through  and  riveted  into  place,  forming  a  particularly  strong 
construction  and  one  which  is  little  subject  to  deterioration. 

The  bearings  are  of  the  plain  ring-oiled  type,  and  ample  reservoirs 
are  provided  so  that  filling  is  not  frequently  necessary.  A  sectional 

view  shows  the  gen- 
eral details  of  con- 
struction. 

It  will  be  noted 
that  the  governor  is 
of  the  plain  centrifu- 
gal type  mounted  on 
the  turbine  shaft,  and 
is  connected  through 
a  simple  lever  direct 
to  the  stem  of  the 
steam  valve.  In  ad- 
dition to  this,  a  safety 
device  is  applied  to 
each  turbine  which 
will  shut  off  the  flow 
of  steam  whenever 
the  speed  exceeds  a 
certain  safe  limit,  irre- 
spective of  the  action 
of  the  governor.  The 
operation  of  the  tur- 
bine is,  therefore,  en- 
tirely automatic. 

The  materials  used 
in  the  construction  of 


17 


Westinghouse  Small  Turbine  Outfits 


these  turbines  are,  of  course  of  the  highest  quality,  and  they  are  built  in 
the  same  shop  with  our  large  turbines.  The  workmanship  is,  therefore, 
beyond  question. 

As  to  sizes  and  capacities,  it  is  not  possible  to  list  these  on  account 
of  the  great  number,  but  as  stated  above,  The  Westinghouse  Machine 
Company  is  prepared  to  furnish  power  turbines  of  this  type  in  any  size 
up  to  500  horsepower  for  any  operating  conditions. 


18 


\ 


\ 

The  Westinghouse  Machine  Company 

V-  Designers  and  Builders  of 

Steam  Turbines  Stokers 

s     A 

Steam  Engines   ~  ^Ga.s  Producers 

Gas  Engines  Pumps 

Condensers  Blowers 

r.-       Turbo  Compressors 


SALES  OFFICES 


A 


New  York ^W  . 165  Broadway 

Chicago .' . .  .  .39  South  La  Salle  Street 

Pittsburgh Westinghouse  Building 

Philadelphia 1003  North  American  Building 

Boston 201  Devonshire  Street 

Atlanta Candler  Building 

Denver Gas  &  Electric  Building 

Detroit 27  Woodward  Avenue 

Cleveland 1117  Swetland  Building 

Cincinnati 1102  Traction  Building 

San  Francisco Hunt  Mirk  &  Co.,  141  Second  St. 

City  of  Mexico Cia  Ingeniera,  Importadora  y  Contratista,  S.  A. 

Havana,  Cuba '.  Galban  &  Company 

San  Juan,  Porto  Rico Porto  Rico  Construction  Co. 

Iquique,  Chile , J.  K.  Robinson  &  Co. 

Toki'o,  Japan Takata  &  Company 

Caracas,  Venezuela H.  I.  Skilton 


GENERAL  OFFICES,  AND  WORKS 

EAST     PITTSBURGH,     PA. 


726303 


UNIVERSITY  OF  CALIFORNIA  LIBRARY 


THIS  BOOK  IS  DUE  ON  THE  LAST  DATE 
STAMPED  BELOW 


AN  INITIAL  FINE  OF  25  CENTS 

WILL  BE  ASSESSED  FOR  FAILURE  TO  RETURN 
THIS  BOOK  ON  THE  DATE  DUE.  THE  PENALTY 
WILL  INCREASE  TO  5O  CENTS  ON  THE  FOURTH 
DAY  AND  TO  $I.OO  ON  THE  SEVENTH  DAY 
OVERDUE. 


MAY   16  1935 

ccf,       o  1939 

Fto      M  ' 

fiPfl 

win 

1 

JUK     fc    19^ 

DEC   75  1040 

10Dec'57CS| 
RECTO  l~U 

HFC  1  v 

